Lighting system and apparatus



March 22, 1949. P. M. KOMM 2,465,103

LIGHTING SYSTEM AND APPARATUS Filed June 2, 1944 2 Sheets-Sheet 1 IN V EN TOR.

. aulM-Komm E72 I By M W March 22, 1949. P.'M. KOMM 2,465,103

LIGHTING SYSTEM AND APBARATUS Filed June 2, 1944 2 Sheets-Sheet 2 INVENTOR. Paul M- Komm Patented Mar. 22, 1949 LIGHTING SYSTEM AND APPARATUS Paul M. Komm, Riverside; 111., assignor to Solar Manufacturing Corporation, New York, N. Y., a corporation of New York Application June 2, 1944, Serial No. 538,413

14 Claims. 1

This invention relates to improvements in-electrical systems having negative resistance char.- acteristics as, for example, lightin systems employing electron discharge types of light'sources as the modern fluorescentlamp.

The invention herein disclosedis of special use in connection with fluorescent lamps of the'heater or cathode type depending. for starting andoperation upon electron emission from the: heaters or cathodes.

An important object of this inventionis to, provide an energizing system for fluorescent lamps of this type which system has built therein the desired ballasting characteristics as well as current supply sources for the cathodes or heaters.

Another object of the invention is the provision of'a circuit arrangement wherein the heating cire cuits for the cathodes or heaters after the lamps are in normal operation consume relatively small quantities of power which condition is automatically attained when the lamps become conductive.

A more specific object of this invention is the provision of an improved form of energizing transformer for fluorescent lamps having. built therein a special energizin secondary for the cathodes or heaters arranged to be subjected to the counter-magneto motive force generatedby the currents flowing in the energizing secondary circuits for the lamps after they becomeconductive, whereby the currents flowing in' the heater or cathode secondary drop to low values.

A more general object of thisinVention' i-sto provide an energizing transformer for fluorescent lights for operating them without'the use of glow discharge relays such as are commonly employed in such systems at thepresent time.

Another broad object of this-invention is the provision of a transformer for the highvoltage operation of fluorescent lamps.

More specific objects of this invention are to provide an improved form of energizing transformer for fluorescent lighting circuits whichois compact, relatively inexpensive to manufacture and eflicient in operation.

Other and more detailed objects of thisinvention will be apparent from the following disclosure when taken in connection with theatta'chedfdrawmgs.

This invention resides substantially in thecombination, construction, arrangementand relative location of parts as will bedescribedindetail below.

In the accompanying drawings,

Figure 1. is a diagrammaticand schematicrillustration of one embodiment of thesinventionnas-applied to the insulated secondary type of circuit showing the heaters or cathodes connected in series;

Figure 2 is a similar view showing an autotransformer type of connection with the heaters or cathodes connected in parallel;

Figure 3 is a schematic and diagrammatic illustration of a modified form of the invention employing the insulated secondary type of transformer with separate secondaries for the heaters or cathodes for both ends of the tubes; and

Figure 4 is an arrangement similar to that of Figure 3 showing the auto-transformer type of connection.

In the system and apparatus disclosed in Figure 1, a shell type of transformer is illustrated comprising a rectangular core [0 of suitable proportions. This core will, ofcourse, be built up of laminations or constructed in accordance with practice common in the art. It includes a central transverse laminated leg ll anchored at its ends t'o'the shell It and forming a core for the primary winding [2, the secondary windings l3 and I4 and the heater secondary winding IS. The construction of these secondaries are well known in the transformer art and, of course, will be provided with the proper number of wire turns to give the proper turns ratio with respect to each other. In accordance with one practical example, the heater secondary l9 will be wound to provide a normal heater voltage of about 9 volts and a normal heater current of about 0.75 amperes. For energization of the primary from the usual volt lighting circuit, the secondaries l3 and I4 will provide a starting voltage of about 350 volts but, of course, all these values'can be changed as conditions require.

At l5 and I6 are magnetic legs extending from the sides of the shell to a point closely adjacent to the core H to provide air gaps and hence a magnetic shunt of variable reluctance. A similar pair of magnetic shunt poles I1 and I 8 extend from the shell 10 and terminate close to the heater Winding l9.

At 20 are diagrammatically illustrated the current supply leads for the primary [2. One terminal of each of the secondaries l3 and M are connected together by the lead 29. The other terminal of the primary I3 is connected through a phasing condenser 23 by means of the conductor 21 to the cathode 22 of the fluorescent lamp XC. The corresponding cathode 25 of another fluorescent lamp XL is connected by the wire v24 to the other terminal of the secondary M. The heaters or cathodes 21 and 28 of these tubes are connected in series by means of the conductors 28 with the heater secondary i9. One of the leads 25 is connected to the lead 29 as shown.

In the operation of this system when the primary i2 is energized the magnetic flux resulting from the flow of current therethrough will thread the heater winding A9 to cause a current to flow in the circuit of the heaters or cathodes 2'! and 28 to bring them to a condition to emit electrons. The potential difference of the secondary i3 is applied between the electrodes 22 and 27 by reason of the connections illustrated, and, similarly, a potential difierence between the electrodes 25 and 28 will be set up by the secondary I l. As the gas in the tubes XL and X becomes ionized a glow discharge will be set up between the respective pairs of electrodes in a well known manner causing currents to flow in the secondaries l3 and M. The current flowing in these secondaries will set up a countermagneto motive force generating a flux, a portion of which, depending upon the design of the transformer, will thread the turns of the heating secondary H9 in opposition to the flux produced by the current flowing in the primary I2. In other words, the shunt magnetic circuit including the shunt poles ll and it will be magnetized by a portion of the magnetic flux pro duced by the current flowing in the primary l2 which will be opposed by a portion of the flux flowing through the same path in an opposite direction by reason of the current flowing in the secondary it. These magnetic fluxes will be out of phase and the resultant voltage across the secondary IE will be reduced to a low value. For example, following the original assumed values, the voltage in the heating secondary circuit will now be of the order of 2.2 volts and the current flowing therein will drop to about 300 milliamperes. Thus during the normal operation of the fluorescent lamps only a negligible amount of power will be consumed in the heater circuit. The shunt paths formed by the pairs of poles l5 and It and H and It! will also provide a path of variable reluctance of limited secondary currents flowing to the lamps in accordance with well known practice. The condenser l3, of course, causes an out of phase operation of the lamp K0 With respect to the lamp XL in order to minimize the well known stroboscopic effect of these lamps.

It will be seen that this arrangement provides a simplified system for the operation of fluorescent lamps providing starting currents for the lamps and automatic current limiting devices for them while eliminating the necessity of using special starting relays.

The arrangement in Figure 2 does not differ a great deal from the arrangement of Figure 1. The shunt poles H and ill have been modified in their physical construction by providing recesses in the ends of the poles in which the heating secondary l9 lies to provide a modified form of magnetic shunt circuit for this heating coil. This variation is but illustrative of the principle that by proper design of the magnetic circuit any desirable operating characteristics within the requirements of such systems can be obtained. Another variation from the arrangement of Figure 1 is found in the connection of the heaters or cathodes 21 and 28 in parallel with the heating secondary l9, as distinguished from the series connection of Figure 1. In this case it will be seen that the lead 29 is connected to one of the leads 20 and one of the leads 26 of the filament heating circuit is connected to the other lead it so as to provide an auto-transformer connection and the proper potential differences between the pairs of heaters Or cathodes 22 and 21. and 25 and 28.

The arrangement of Figure 3 is different from that of Figure 1 in that in place of a single cathode or heater secondary I9 there are provided three heater secondaries 30, 3| and 32. In this case the shunt poles l1 and 18 are provided with suitably shaped pole ends so as to subject all of these coils to their proportionate share of magnetic flux flowing through the shunt path. The two heaters or cathodes 22 and 25 are connected in series by means of the conductors 33 to the terminals of the secondary 30. One of the leads 33 is connected to the common lead 29 for the lamp operating secondaries I3 and M. The cathode or heater 2'! is connected by the leads 35 to the secondary 3|, as shown. One lead of the secondary i3 is connected through the phasing transformer 23 to one of the leads 35, as shown. The cathode or heater 28 is connected by the leads 34 to the terminals of the third heating secondary 32 and one of these leads is connected to one of the terminals of the secondary M, as shown. Thus in this arrangement all of the heaters or cathodes, that is, those for each end of each tube, are conductively connected so as to be supplied with heating currents to render them electronically emissive during starting of the lamps. The connections as shown and as before apply the high voltage operating potentials between the pairs of electrodes 25 and 28, and 22 and 21, as before, and the phasing condenser 23 has the same function as it does in the previous arrangements. The heating secondaries 30, 3| and 32 function as before supplying proper energizing currents to the cathodes or heaters during starting and are subjected to the counter-flux resulting from the flow of current in the secondary l4 when the tubes become operative to drop the voltage in the heating circuits to a low value during the normal operation of the lamps.

In the arrangement of Figure 4, the apparatus is similar to that of Figure 3 but in the former the circuits are cross-connected to provide an auto-transformer type of system as distinguished from the insulated secondary type of Figure 3. One of the primary leads 20 is connected, as shown, to the common lead 28 or the secondaries l3 and I4. One of the leads 33 for the cathodes 22 and 25 is connected to the other lead 20, as shown. One of the leads 34 for the cathode 25 is connected to one terminal of the secondary M, as shown. One of the leads 35 for the cathode 22 is connected to one terminal of the secondary l3 through the phasing potential 23, as shown. This arrangement provides a system similar to that of Figure 3 differing only in the auto-transformer connection with the attendant characteristics of this type of operation.

The winding for the heater coils, for example the coil 19 of Figure l is preferably of insulated iron wire, although copper, and wires of other materials can be used. Iron wire is preferable because of the better regulation of the heating circuit which is secured.

From the above description, it will be apparent to those skilled in the art that the subject matter of this invention is capable of considerable variation without departure from the novel scope thereof, and I do not, therefore, desire to be strictly limited to the disclosure as given for purposes of illustration, but rather to the scope of the claims granted me.

What is claimed is:

1. In a system for operating electron discharge devices, the combination including a transformer comprising a magnetizable core, a primary energizing winding on said core, a pair of high voltage secondary windings on said core, a pair of magnetic shunts forming part of said core and positioned between said primary and said secondaries respectively, a low voltage secondary winding on said core positioned in the flux path of one of said shunts, a pair of discharge devices each having a pair of cathodes at least one of which is filamentary, circuit means for connecting each pair of cathodes across one of said high voltage secondaries respectively, and circuit means for connecting the filamentary cathode of each device to said low voltage secondary to heat it.

2. In the combination of claim 1, said primary winding being interconnected with said secondaries to form an autotransformer connection.

3. In the combination of claim 1, said filamentary cathodes being connected in series with said loW voltage secondary.

4. In the combination of claim 1, said filamentary cathodes being connected in parallel with said low voltage secondary.

5. In a system for operating electron discharge devices, the combination including a transformer comprising a magnetizable core, a primary energizing winding on said core, a pair of high voltage secondary windings on said core, a pair of magnetic shunts forming part of said core and interposed respectively between said primary and secondary windings, three low voltage secondary windings on said core so as to be linked with the flux of one of said shunts, a pair of discharge devices each having a pair of filamentary cathodes, circuit means for connecting each pair of cathodes across said high voltage secondary windings respectively, circuit means for connecting one cathode of each device to two of said low voltage secondaries respectively to energize them, and circuit connections for connecting the other cathodes of each device to the third low voltage secondary winding to energize them.

6. In the combination of claim 5, said last pair of cathodes being connected in series with said third low voltage secondary winding.

7. In the combination of claim 5, said primary and secondaries being interconnected to form an autotransformer connection.

8. In the combination of claim 1, said low voltage secondary winding being mounted on said core directly in the path of one of said magnetic shunts.

9. In the combination of claim 1, said low voltage secondary winding being composed of iron mm.

10. In the combination of claim 5, said low voltage secondary windings being composed of iron wire.

11. A transformer comprising a core, a primary winding mounted centrally of said core, a pair of high voltage secondary windings mounted on said core on opposite sides of said primary winding, magnetic shunts forming parts of said core and lying respectively between said primary and secondary windings, and a low voltage secondary winding mounted on said core so as to be linked by the flux of one of said shunts.

12. In the combination of claim 11, said low voltage winding being composed of iron wire.

13. A combination as disclosed comprising a magnetizable core having an energizing winding and a high voltage secondary winding thereon in spaced relation, a magnetic shunt forming part of said core and lying between said windings, and a low voltage winding on said core in position to be linked by the flux of the shunt.

14. A combination as disclosed comprising a magnetizable core having an energizing winding and a high voltage secondary winding thereon in spaced relation, a magnetic shunt forming part of said core and lying between said windings, a low voltage winding on said core in position to be linked by the flux of the shunt, a discharge device having a pair of cathodes, circuit means for connecting said cathodes across said high voltage secondary Winding and circuit means connecting at least one of said cathodes to said low voltage winding for energization thereby.

PAUL M. KOMM.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,741,493 Babson et al Dec. 31, 1929 1,884,386 Thordarson Oct. 25, 1932 1,977,231 Erickson Oct. 16, 1934 2,269,978 Kronmiller Jan. 13, 1942 2,298,935 Freeman Oct. 13, 1942 2,302,213 Hall Nov. 17, 1942 2,312,867 Boucher Mar. 2, 1943 2,317,844 Boucher & Kuhl (a) Apr. 27, 1943 2,354,879 Ranney Aug. 1, 1944 2,355,360 Boucher & Noble (a) Aug. 8, 1944 2,370,635 Bridges Mar. 6, 1945 

